Hydraulic power transmission



. C. E. PAINE.

HYDRAULIC POWER TRANSMISSION.

AIPLICATION FILED JUNE I4, 1920.

Patented Apr. 5, 1921.

2 SHEETS-SHEET I.

IIIIIIIIII llnumm A lr IIIIA 4.4M .254m LM C. E. PAINE.

HYDRAULIC POWER TRANSMISSIUN.

APPLICATION FILED IUNE14, I920.

Patented Apr. 5; 1921.

2 SHEETS-SHEEI 2.

NI S

uru'llEDy STATES .PATENTfoI-Flca CECIL E. PAINE, IOI' BATH., MAINE'.

HYDRAULIC rownn Transmission.

'Specification of Letters Patent.

Patented Apps, 1921.

Applicationled .Tune 14, 1920. Serial No. 388,930.

T o all wbb/m, it may concern Be it known that I, CEcrL E. PAINE, a citizen of the United States, and resident of Bath, Maine, have invented certain new and useful Improvements in Hydraulic Power Transmissions, of which the following is a the same.

specification.

My present invention relates to improvements 1n power transmitting means -of the fluid type and is designed more especially..

for use vin connection with apparatus `for steering ships, though not limited to such use, the invention being in factan improvement upon the apparatus disclosed in Lety ters Patent of the United States granted to me on the 8th day of July, 1919, No. 1,: ,09,076.y g jv The invention aims to provide a simple, economical, durable and ecient form of apparatus in which a non-reversible pump may be used to secure movements .of the part to4 be moved in either of two directions, and .in which, while the part to be moved is held stationary, with the control valve closed, there will be practically no pressure on-the oil or other liquid which would tend to heat The invention valso aims to'provide a construction in which upon movement'nf the controlling valve the full-force of the pump will be instantly available and which will 'be automatically responsive to reduce, the

pressure to a degree commensurate with the resistance offered, and the stroke of they pump reduced toyzero when the maximum@ resistance forwhich the apparatus is adjusted, is encountered.

With these and other objects'in view the invention includes the novel features of con'- structipn and arrangement and combination of parts hereinafter described and particularly defined by the appended claims.

An embodimentof my invention is illustrated in the accompanying drawings, in-

understood by those skilled in the art. The pump 1s lllustrated conventionally and I have selected as a convenient type of pump one having a, tilting head, .the rocking of which in the proper direction will vary the pump action from zero to maximum and vlce-versa, such tiltmg head being indicated at 2. i

The'pump is provided with an operating shaft which is designed to be coupled to'v .any suitable continuously running and nonreversible prime mover (not shown). The

forcing or delivery and suction sides of the l' pump are connected by flow and return pipes 9 and 11 with a valve casing 10 which as an interior valve chamber preferably of cylindrical form within which is located the spoolshaped reversing valve 6. Th1- delivery pipe 9 is connected with the .central portion of the valve chamber so as t0 be in communication with the 'annular space formed around the reversing valve between the heads 6b, 6c thereof, while "the return pipe 11 is connected with the ends of said valve chamber.

The pipe 11 may conveniently beconnected directly to one end of the valve chamber as shown in Fig. 1, and this end of` the chamber placed in communication with the opposite ende bya`-` passage indicatedfby dotted lines Fig. v1 l'thel end ports being shown at 8"-8c.Y 4

'The valve casing is provided with ports 10" and 10e which are designed to be conf'nected by pipes B and C with the opposite sides of the reversible motor or ram towhich movement. is to be imparted such for eX- sol 'ample asa rudder operating ram indicatedV y*conventionally in the drawings and desig .nated ,Ram. 4The ports 10b and 1()c are located in such position that when the reversing valve is in neutral position, -as showniin Fig. 1, the heads 6b and 6c aline respectively with the .ports 10b and V10c and `the relativefdimensions are such that in this Vposition the flow of oil or other li uid to and from the pipes B and Cy is cut o .When, therefore, the reversing valve is in such neutral osition the fluid will be shut up or confined.) in the pipes B and C and the ram andthe movable element of the ram is therefore locked against movement, which, in the case of a rudder actuating ram would result -in vthe rudder being held immovable.

By-passes b and 0 are provided in connection with the heads 6b and 6c of theevalve, which, when the valve is in neutral position place the central portion of the valve chamber, and the end portions in communication,

and hence the delivery pipe 9 in unobstruct-` ed communication with the ends of the valve chamber and therefore with the return or suction pipe 11. 1

The liquid is therefore free to circulate 10` freely through the pumpand valve chamber and connecting pipes,without any appreciable pressure thereon sothat there is no tendency for it to heat up,and the pump can be run continuously at maximum speed 15. with no detrimental effects such as the heating above referred to and without, any danger of stalling the motor.`1 l

The valve is provided with a valve stem extending through one end of the valve casing as indicated at 13, which stem maybe i connected with any suitable operating mechanism, such as :shown for example in my prior patent aforesaid.

The by-passes b and c are so arranged that movement of the valve in either direction to open the ports l0band 10c instantly closes both by-passes. This may be conveniently accomplished by providing the heads 6b and 6c with crescentshaped reduced or rabbeted portions c and providing corresponding recesses and c in the inner wall of the valve casing.

` Thus when the valve is moved in either direction` tlieby-passes. are immediately closed and the entire volume of liquid from the pump lat maximum flow or pressure is at once directed into one or the other of the ports 10b and 10c according to the `direction of movement of the valve, the port not so 40 connected being placed in communication with the suction side of the pump.

lIn order to cut down the flow according to requirements and to prevent the building A up of excessive pressure the central or inlet portion of the valve chamber is connected by a pipe 4 with an automatic pump con,- trolling device as-follows:` v

Pipe 4 communicates (with a cylinder or chamber 14 secured to the pump casing within which worksa reciprocating stem or piston member 16, passing through a suitably packed or bushed opening in the cylinder casing as indicated at 22 and being connected inside said casing with the tilting head of the pump. p V

Ar spring 15, bearing at its inner" endagainst the endlv wall of the casing, and at its outer end against Aa washer or contact plate or member 17 on the rod or stem 16 tends to press the stem outwardly and tilt the pump head in a 'direction to cause the pump to give a'maximum flow of liquid.

As pressure is vbuilt up in the cylinder 14 .l .due to thev liquid backing up in pipe 4, the 65 tilting headl'willbe swung back toward zero u to latg') beyond the maximum'desired. 3^

The pressure of the springv may be adjusted .by nuts 18 threaded on the outer portion of the Stein against which nuts the member 17 be-ars.

The'maximum output of the pump ma-y be regulated by an adjusting nut 19 threaded into a recess in the end wall orI closing cap 14"l of the cylinder 14 and adapted to act as a stop for the outer end of the stem.

" The limit of inward movement of the stem may be accurately vadjusted by an adjusting collar 20 threaded on the stem and locked in position by loc-k nut 21, said col- -lar contacting against bushing 22 and .ac-

curately determining the zero Vposition of p the tilting head.

It will be understood that any suitable meansmay be provided for operating the valve, such for example. as shown in my aforesaid patent,.such operating means being omitted from the present disclosure as forming per se no part of the `present invention.

Having thus described my inventioniwhat` I claim 1s 1. In combination, a'v driven motor, a'continuously operable variable stroke pump for supplying motive fluid to operate said motor, a reversing valve for reversing the flow of fluid between the pump and motor, and

position thus reducing the stroke of the pr'event pressure being accumumeans for by-passing the liquid around said reversing valve when the latter is in neutral position. 1 'I 2. In combination, aldriven motor,a continuously operable variable stroke pump for fluid between the pump and motor, pressure operated means for varying the stroke of the pump to prevent accumulation of excessive pressure and means enabling the m0- tive fluid to flow freely from the discharge to the intake of said pump to eliminate pressure when the valve is in neutral position.

4. In combination, a continuously perable variable stroke pump, avalve casing having a central portion connected with the delivery side of said pump, and end por-- tions connected with the suction side thereof, a driven fluid motor having fluid transmitting connections to said valve casing, a 13e reversing valve having heads adapted to reverse the connections to said driven motor, said heads in neutral position of thevalve cutting off said connections to the driven motor, said lheads having rabbeted portions and said valve casing corresponding recesses forming by-passes around the heads of said valve when the latter is in neutral position.

5; In combination, a reversible motor, a continuously operable irreversible pump having a tilting headfor varying the stroke of the pump, and provided with connections for supplying fluid to said motor, valve means for reversing said connections and also for cutting off the fluid connections to1 15 In testimony whereof, I aliix my signature. l20

oEoiL n. PAINE. 

